A Gridless Routing Algorithm Based on Routability Evaluation

Recent packaging technologies have made PWB layout complicated . Increasing connections between a lot of surface mounted devices (SMD's) make it difficult to apply conventional routing algorithms, such as maze running or line-search algorithm . Since they search and fix each net path one by one, they cannot achieve sufficient performance . This paper describes a gridless routing system, which evaluates influences of all nets including unrouted nets. This system also employs hierarchical routing process for bus net routing . Experimental results have shown the effectiveness of this system .